you have orders to give a patient 20 mg of a certain medication the medication is stored 4 mg per 5 ml dose how many milliliters will need to be given

HESI A2

HESI A2 Math Practice Test 2022

1. You have orders to administer 20 mg of a certain medication to a patient. The medication is stored at a concentration of 4 mg per 5-mL dose. How many milliliters will need to be administered?

A. 30 mL
B. 25 mL
C. 20 mL
D. 15 mL

Correct answer: B

Rationale: To administer 20 mg of the medication, you would need 25 mL. This calculation is derived from the concentration of 4 mg per 5 mL. By setting up a proportion, you can determine that for 20 mg, 25 mL must be administered as follows: (20 mg / 4 mg) = (x mL / 5 mL). Solving for x results in x = 25 mL. Choice A is incorrect because it miscalculates the proportion. Choices C and D are incorrect as they do not account for the correct concentration of the medication.

2. Express the ratio of 12:15 as a percentage.

A. 58.80%
B. 62%
C. 75.25%
D. 80%

Correct answer: C

Rationale: To express the ratio 12:15 as a percentage, you need to find the total parts in the ratio (12 + 15 = 27), then divide one part by the total (12 ÷ 27 = 0.4444). Finally, convert the decimal to a percentage by multiplying by 100 (0.4444 x 100 = 44.44%). Therefore, the ratio 12:15 is equivalent to 44.44% when rounded to two decimal places, which is closest to 75.25% among the answer choices. Choices A, B, and D are incorrect as they do not represent the correct percentage equivalent of the ratio 12:15.

3. If a parent changes their baby 6 times a day, how many diapers will be needed in a year?

A. 2190 diapers
B. 2100 diapers
C. 2160 diapers
D. 2140 diapers

Correct answer: A

Rationale: To calculate the number of diapers needed in a year with 6 diaper changes per day, multiply the daily diaper changes (6) by the days in a year (365): 6 x 365 = 2190 diapers required. This calculation ensures an ample supply of diapers for maintaining the infant's hygiene and comfort. The other choices are incorrect because they do not accurately account for the number of diaper changes per day multiplied by the days in a year. Choice B (2100 diapers) is too low, while choices C (2160 diapers) and D (2140 diapers) are too high based on the calculation. Understanding the frequency and quantity of diaper changes is crucial for supporting the infant's health and well-being. Therefore, the correct answer is 2190 diapers.

4. What number is 15, if it is 20% of that number?

A. 3
B. 45
C. 75
D. 300

Correct answer: B

Rationale: To find the number that 15 is 20% of, we set up the equation: x * 0.20 = 15. Solving for x, we get x = 15 / 0.20 = 75. Therefore, 15 is 20% of 75. Choice A, 3, is too small to be 20% of 15. Choice C, 75, is the result of the correct calculation. Choice D, 300, is too large to be 20% of 15.

5. What is the result of dividing 5 3/4 by 1/2?

A. 11 & 1/2
B. 2 & 3/8
C. 3 & 1/8
D. 18

Correct answer: A

Rationale: When dividing fractions, you multiply by the reciprocal of the divisor. To divide 5 3/4 by 1/2, you multiply 5 3/4 by 2/1 (reciprocal of 1/2) to get 23/4 * 2/1 = 46/4 = 11 1/2. Therefore, the correct answer is A. Choice B (2 & 3/8) is incorrect as it does not result from dividing 5 3/4 by 1/2. Choice C (3 & 1/8) is incorrect as well. Choice D (18) is not the correct result of the division performed.